Thanks very much for the very detailed info
I have a small confession though - while doing another little job I noticed the rubber washers on the cycle wing had perished away and that the wing had been clattering up and down the screw between wing stay and screw head, to the extent that it's now cracked from hole-to-hole. Now I've made a new pair of rubber washers, the noise I thought had been coming from the FR shock magically appears to have stopped and the ride seems not quite as bad as I thought Obviously I was paying more attention to what I was hearing than to what I was feeling.
Still think the bushes could do with a refresh as the bits I can see look pretty tired, but I'll hold off on large scale expenditure for a bit - other than replacing the front wing!